在Flavobacterium johnsoniae中翻译prfB时编程移的分析
Fawwaz M Naeem1,2, Bryan T Gemler2,3, Zakkary A McNutt1,2
1Ohio State Biochemistry Program, The Ohio State University, Columbus, Ohio 43210, USA.
概括
细菌杆菌的核糖体通常会避开Shine-Dalgarno (SD) 序列,但prfB基因使用它们进行编程的+1框架转移. 这项研究揭示了Flavobacterium johnsoniae中prfB框架转移率很低,并且经常发生在没有SD-anti-SD配对的情况下,影响细胞健康.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
背景情况:
- 由于16S rRNA序列化,细菌菌类核糖体通常不会识别Shine-Dalgarno (SD) 序列.
- 在 Bacteroidia 中的 prfB 基因通常包含一个具有 SD 序列的编程 +1 移位点,在翻译启动中产生悖论.
研究的目的:
- 研究Flavobacterium johnsoniae中prfB自我调节的机制和效率.
- 确定SD-anti-SD (ASD) 配对和核糖体蛋白bS21在Bacteroidia中的prfB框架转移中的作用.
- 探索prfB跨细菌群体的框架转移机制的进化保护和变异.
主要方法:
- 在F. johnsoniae和Escherichia coli中对prfB框架转移效率的比较分析.
- 在F. johnsoniae中对prfB和核糖体蛋白bS21的局部定向突变发生.
- 评估与原生和异构SD序列的移.
- 在压力条件下对F. johnsoniae突变体的表型分析 (帕拉克瓦特,链杆菌素).
- 在广泛的细菌物种中对prfB框架移位点的生物信息分析.
主要成果:
- 与大肠杆菌 (∼50%) 相比,F. johnsoniae的prfB移效率较低 (∼7%).
- 核糖体蛋白bS21的突变或切断显著增加了F. johnsoniae中的框架转移,表明ASD封存的作用.
- 在没有SD的异质序列中,F. johnsoniae prfB的框架转移可以有效地发生,这表明SD独立的机制.
- 影响移或SD结合的染色体突变会在特定的压力条件下导致微妙的生长缺陷.
- 在prfB框架移位点中,SD序列损失在细菌菌株中广泛存在,与全基因组SD使用没有明确的相关性.
结论:
- 在F. johnsoniae中,PrfB移主要在标准实验室条件下独立于SD-ASD配对运行.
- 核糖体蛋白bS21在通过ASD封存抑制移效率方面发挥着至关重要的作用.
- 自主调节机制和SD元素都对F. johnsoniae的健康有所贡献,突出了prfB框架转移的功能意义.
- 在细菌的翻译控制机制中存在显著的进化分歧,特别是在SD序列利用方面.
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